package leetcode.problems;

import org.junit.Test;

import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;

/**
 * Created by gmwang on 2020/2/6
 * Unique Number of Occurrences
 * 唯一的重复值
 */
public class UniqueNumberofOccurrences {
    /**
     * Given an array of integers arr, write a function that returns true if and only if the number of occurrences of each value in the array is unique.
     *
     *
     *
     * Example 1:
     *
     * Input: arr = [1,2,2,1,1,3]
     * Output: true
     * Explanation: The value 1 has 3 occurrences, 2 has 2 and 3 has 1. No two values have the same number of occurrences.
     * Example 2:
     *
     * Input: arr = [1,2]
     * Output: false
     * Example 3:
     *
     * Input: arr = [-3,0,1,-3,1,1,1,-3,10,0]
     * Output: true
     *
     *
     * Constraints:
     *
     * 1 <= arr.length <= 1000
     * -1000 <= arr[i] <= 1000
     **/
    public boolean uniqueOccurrences(int[] arr) {
        boolean result = false;
        Map<Integer, Integer> tmp = new HashMap<>();
        for (int i = 0; i < arr.length; i++) {
            Integer aDefault = tmp.getOrDefault(arr[i], 0) + 1;
            tmp.put(arr[i],aDefault);
        }
        Collection<Integer> values = tmp.values();
        HashSet<Integer> set = new HashSet<>(values);
        if(set.size() == values.size()){
            result = true;
        }
        return result;
    }
    @Test
    public void Test(){
//        int [] arr2 = {1,2};
//        int [] arr2 = {1,2,2,1,1,3};
        int [] arr2 = {-3,0,1,-3,1,1,1,-3,10,0};
        boolean occurrences = uniqueOccurrences(arr2);
        System.out.println(occurrences);
    }
}
